Prop Shaft Connection to VD Trans

J

J Levine

New Member
Oct 5, 2006
753
New Jersey
Boat Info
1995 Sea Ray 370 Sundancer
Engines
Mercruiser 7.4L Blue Water inboard V Drives
I am going to be removing my prop shafts this fall/winter to install new shaft seals. I am assuming that the connection between the prop shaft and the transmission involves a shaft key that engages the shaft to the collar that then bolts to the output flange of the transmission. I know I have a nut on the end of the shaft up against the collar with a cotter pin. Is this correct? I dont see any set screws in the collar. Is this a correct description of how the shaft is attached to the transmission? Any advice on taking this apart and pulling the shaft out? I know I have to clean the shafts to protect the cutlass bearings, not to mention inspect the cutlass bearings which were replaced 5 years ago.
 
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OK 44 hits and no answers, must be a problem with the author's lousy description. I know someone out there has taken the prop shaft out of a gas powered Sea Ray with V Drives and knows the answer. Let me try to re-ask the question....

How is the forward end of the prop shaft connected to the output flange of the transmission? I do not see any set screws and the end of the shaft has a nut that is flush with the prop shaft side of the output flange so I assume there is a key way in the flange and a key way in the shaft with a key holding them together?

Does this require the kind of force needed to pull a propeller or should this thing come apart easily once the nut is removed?
 
I will be happy to give you the step by step but it will be later tonight. What type of shaft seals do you want to install?

-John
 
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Their are at least two types of hubs which are available for your boat. I'm not sure of your boats history and whether or not the hubs are original or not. A picture would be helpful.

1) remove the prop.

2) depending on the seal type (tides, pss or packing glands) different procedures are called for.

3) the shaft has an interference fit and is keyed with the hub. Normally when shafts are replaced I get the hubs done to match. Most hubs have setcrews to hold the shaft in place. Some have a setscrew and a clamping bolt. The setscrews and if present the clamping bolt need to be removed.

The clamping bolt hub is easier to work with because you can spray penetrating oil into the split in the hub to aid in step 5.

4) If you are just replacing the seals and not the cutlass bearings then you only need to clean five inches of the shaft in front of the cutlass bearing.

5) This is where it will really fight you or you might get lucky. The bad news first: Corrosion can seize the shaft in the hub and make it impossible to remove. In those cases, there is little choice but to cut the shaft, remove and replace with a new shaft and hub.

I'm hopeful you won't have to do that.

What you will need is a shaft puller. It is a slide hammer that threads on to the prop shaft (where the prop nut goes) and does a great job of removing most shafts. You can also try to do it the old school way by splitting the hub from the transmission flange and using a variety of bolts, nuts, washers and sockets to press the shaft from the hub using the transmission flange. This is difficult to do on your boat with V-Drives. Do not beat on the hub or transmission flange with a hammer to "crack it loose" unless you want to deal with a major repair bill.

A shaft puller is the way to go.

6) Once the shaft is free from the hub, you can perform the rest of the work with little drama.

I would inspect the cutlass bearings because it is much easier to deal with them at this point. Let me know if you have any questions.

-John
 
My hub was retained to the shaft w/ four bolts. The hub was keyed to the shaft.

The port side came right apart. The starboard required more effort. A follow-up inspection revealed the starboard hub tapered bore had a small internal lip, causing it to hang up.

Once the hub is removed, the shaft may slide rearwards.

Mine had not only the shaft seal, but a spare in a seal carrier. Use a seal protector on the spare. The keyway can nick the seal, causing it to leak. The protector prevents that damage.

The spare was made active and the new was installed as the spare.

The stock bolts had been over-tightened and removal caused rounding. Those were replaced w/ new anti-corrosion plated class 8 bolts, nuts and lock washers.
 
Thanks for the feedback. I have only this one attached picture available right now of the hub on the port side. I find no set screws, clamping bolts or splits in these hubs. It appears to me that the hub is keyed to the shaft and retained by the nut on end of the shaft. I am have a slide hammer but not the proper hardware to connect it to the prop end of the shaft, but I am sure I could figure out how to do that.

The boat was originally built with standard shaft packings. A previous owner removed the packings and added Tides Strong Seals which, according to the Tides web site were manufactured prior to 2000. In the spring of 2005 I had a yard replace the starboard lip seal which was leaking badly and install a extra seal and carrier kit at the same time. This is the only repair I have ever paid to have done in the 5 years I have owned the boat. Now the port lip seal is leaking. After a lot of research I have decided to replace the old Tides units with PSS seals as they appear to be both superior in design and function and easier to work on. I can buy two PSS seals for less than I paid in parts and labor to have one Tides lip seal replaced. I am going to do this over the winter so I will have pleanty of time to mess with it if pulling these shafts proves to be a problem. I know the Starboard shaft was removed or at least pulled back in 2005 to replace the lip seal.

Appreciate any additional guidance on pulling the shafts back to replace the seals.

I had the cutlass bearings replaced by the seller when I bought the boat, but I believe they were probably pressed in using a hydraulic tool that avoids the need to remove the shafts.
 
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Got it. A picture avoids the guesswork.

Release the cotter pin, back the nut off and use the shaft puller to pull it out. This configuration requires you to pull most of the shaft out (it goes through the transmission) to gain access to the area you want to work on. It is keyed inside the hub. Once the shaft is removed, I would also index (mark the both flanges) and pull the hub to debur any rough spots.

It's late on the East Coast. I will post a few tricks for the PSS seals tomorrow.

-John
 
Remove the cotter pin.

Remove the large nut.

Remove the four bolts / nuts that attach the hub to the transmission flange.

Separate the hub from the shaft.

Remove the key from the keyway.

Now the shaft may be removed.
 
wingless,

The trick is getting the hub off the shaft. In the method you describe did you using a hub press (which connects to the hub with bolts and nuts) or did you use a shaft puller on the shaft that did not come off the hub easily?


In regards to the PSS seals, I am a huge fan of their design. Installation is very straightforward.

1) Mark and remove the shafts from the boat. I know this means you need to clean them to get them through the cutlass bearings but the next part is critical to the success of the effort.

2) Debur the keyway and polish/debur any imperfections on the shaft to the point where it enters the shaft tube. This is much easy to do with the shaft out of the boat. The sealing collar uses two nitril o rings to seal to the shaft. A sharp edge on the keyway or shaft imperfection can tear the o rings as you install the sealing collar.

3) Install the bellows on the shaft tube with the cooling water port facing in the direction you want.

4) Feed the shaft back through the cutlass bearing, through the shaft tube and newly installed bellows.

5) Install the o rings in the sealing collar. I use dishwashing soap to lubricate the o rings and the shaft. Nitril will breakdown with a petroleum based product, so dishwashing soap makes a great lubricant.

6) Slide the collar down the shaft without compressing the bellows as you move the shaft toward the hub.

7) Install the keyway and reattach the hub to the transmission.

8) The sealing collar employs stacked set screws to lock it on to the shaft. Once the shaft is secure, slide the sealing collar down the shaft until it makes contact with the carbon seal. At this point, I wrap a piece of electrical tape around the shaft in front of the sealing collar to mark a "zero reference" point. You can also use a Sharpie but I find it rubs off and I like to have a permanent reference point to make sure the collar hasn't slipped over time.

9) Continue to slide the collar down and compress the bellows. I usually compress the bellows 1" to 1.25" from the zero reference point. Tighten the first set of setscrews to lock the collar in place. Then tighten the second set of setcrews on top of the first set.

10) Connect the raw water cooling line to a suitable pressurized raw water source. You can also install a cross-over to the other engine although I think that is overkill for most applications.

11) Put the prop on and you are back in business.

12) When the seal first breaks in, it will draw a thin black line on any surface within a few inches of the seal. That is normal. It is the face of the carbon surface breaking in and the line is the excess material. It is strange when you see it for the first time.


While there are other solutions, I think PSS got it right with their design. A dry bilge is a beautiful thing.

-John
 
John

Wow what great advice, man it pays to learn from experience. After reviewing all the various options available to replace the Strong Seals I am sold on the PSS design and glad you agree. I have reviewed the instructions that PSS has posted on their website, but yours are even more detailed. As far as a water source, I already have that in place with the Strong Seals so I am going to just reuse the same hoses. I appreciate your advice to completely remove the shafts. I figured when you said they only had to be pulled back 5" you were forgetting I have the V drives. How should I connect my slide hammer to the shaft at the prop end to pull the shaft of do you think I am not need the hammer at all?

Also do you think there is any value in having the shafts inspected while they are out at a shaft shop? I am thinking about have them checked for stress crackes and straightness?
 
J Levine said:
John

Wow what great advice, man it pays to learn from experience. After reviewing all the various options available to replace the Strong Seals I am sold on the PSS design and glad you agree. I have reviewed the instructions that PSS has posted on their website, but yours are even more detailed. As far as a water source, I already have that in place with the Strong Seals so I am going to just reuse the same hoses. I appreciate your advice to completely remove the shafts. I figured when you said they only had to be pulled back 5" you were forgetting I have the V drives. How should I connect my slide hammer to the shaft at the prop end to pull the shaft of do you think I am not need the hammer at all?

Also do you think there is any value in having the shafts inspected while they are out at a shaft shop? I am thinking about have them checked for stress crackes and straightness?
Click to expand...


"Also do you think there is any value in having the shafts inspected while they are out at a shaft shop? I am thinking about have them checked for stress crackes and straightness?"

I do, simple 10-15 minute test on each with a dialer..but what do I know, I have a red ball ;-)
 
PlayDate said:
.......

10) Connect the raw water cooling line to a suitable pressurized raw water source. You can also install a cross-over to the other engine although I think that is overkill for most applications.

..........
Click to expand...

John:

All great information but why do you feel it is overkill to have a crossover?

I've had the 'oppurtunity' to limp in on one engine twice this year (not my boat, a neighbor's), and it was very nice to not have to worry about locking the stalled side's prop shaft thanks to the crossover.
 
osd9 said:
John:

All great information but why do you feel it is overkill to have a crossover?

I've had the 'oppurtunity' to limp in on one engine twice this year (not my boat, a neighbor's), and it was very nice to not have to worry about locking the stalled side's prop shaft thanks to the crossover.
Click to expand...

We have dripless shafts, no crossover

We have limped in 4 times in 2 years on one engine. In 3 of the cases I could not run the 2nd engine. In those 3 cases I did not lock down the shaft on the engine not running. We have had no "known" issues with this, no leaks, nothing I can see.

What would one see if there was a resulting problem?
 
Greg,

It is my understanding that checking straightness with a dial indicator while the shaft is installed in the boat is not of much value and that this should be done in a shop on the bench top... thats what I have heard but not much else on the subject. I dont really suspect I have an issue but all the same with boat out of the water for 5 months and no rush on getting this done I am thinking about doing it. I have had the props serviced twice (prop scan) over the years and the shop I use will also inspect shafts. I need to call them to find out how much this costs. I have thought about the cross over in the past but since I carry on board the correct open end wrench (a big one) that I can place on the nut on the transmission end and it will then fowl the shaft against the stringers and keep it from rotating. Pretty easy way to do this so I have never gotten too excited about doing a cross over.
 
Never thought about an open end on the nut, was told to use a pipe wrench, which we now carry on board.

"correct open end wrench (a big one)"

You recall the size?
 
mrsrobinson said:
...What would one see if there was a resulting problem?
Click to expand...


It depends on how long you had to 'limp' home.

If the shaft on the stalled engine continues to turn for a long period you can overheat the seal and shorten it's life. May not be something you would see right of way.

Also, and crossover doesn't solve/help this, you have to worry about your transmission. DIfferent manufacturers have different criteria and specs when 'freewheeling'.
 
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